sip - SIP 和 SIPS URI 之间的区别？

Question

我正在阅读 SIP RFC 3261。我没有得到 sip uri 和 sip uri 之间的区别。有人可以帮忙吗。

Answer 1

来自 rfc3261 的第一个注释：

The format for a SIPS URI is the same, except that the scheme is
"sips" instead of sip.

第二个注意事项，我想您的问题可以在第 26.2.2 节（SIPS URI 方案）中找到，即：它表明所有跃点都需要保护，最常见的是通过 TLS 链接。

When used as the Request-URI of a
request, the SIPS scheme signifies that each hop over which the
request is forwarded, until the request reaches the SIP entity
responsible for the domain portion of the Request-URI, must be
secured with TLS; once it reaches the domain in question it is
handled in accordance with local security and routing policy, quite
possibly using TLS for any last hop to a UAS.  When used by the
originator of a request (as would be the case if they employed a SIPS
URI as the address-of-record of the target), SIPS dictates that the
entire request path to the target domain be so secured.

当 sips 出现在 To 或 From 标题中时，其他规则适用。例如，当 sips 出现在 To 标题中时，它表示“希望”使用安全链接。在 Request-URI 中使用时，它是必须的。

使用 sip 时，您可能还需要在联系人标题中使用 sip。sips URI 最终将在 Request-URI 中用于对话中的其他请求，因此您必须关心在 Contact 标头中使用正确的 sip/sips。